SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cbc0937302380eacd8242d38d0b66139c9a9f0f9fc6d52e14fe625098ac17098' 
  AND token = 'bIWEIuCreDdDXDhbx4KUcaVCgsjkKOdEu0Y862EYDPE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}